Cervical laminoplasty is a surgical technique that is used to remove pressure from the spinal cord in the neck area. Pressure on the spinal cord is usually due to spinal stenosis that may be caused by degenerative changes, arthritis, bone spurs, disc herniations, ossification of the posterior longitudinal ligament (OPLL), tumors, or fractures, among others. Frequently, spinal stenosis occurs simultaneously at multiple levels of the cervical spine. If the pressure is severe enough, myelopathy can develop. In this case, laminoplasty may be applied for removing the pressure, allowing the spinal cord to heal, and reversing the symptoms.
Laminoplasty involves cutting the lamina on both sides of the vertebra and swinging one side of the cut bone away in order to hinge open the spinal canal. This is called the “open door” procedure, where in one side of the lamina a complete through-cut is performed and in the other side a groove or partial cut is formed and the lamina is then hinged opened about the groove in order to increase the diameter of the spinal canal and remove the applied pressure on the spinal cord. Part of the lamina and/or the spinous process may be removed during laminoplasty. The hinged lamina is supported in the open position via a plate that is inserted and fixed between the facet and the cut end of the lamina.
Typically, the surgeon needs to determine the size of the opening and the size of the plate to use in order to increase the diameter of the spinal canal sufficiently so that the pressure on the spinal cord is removed. Flexibility in the size and the overall dimensions of the plate is desirable in order to accommodate various size vertebras.